EN 50405:2015

SLOVENSKI STANDARD
01-marec-2016
1DGRPHãþD
SIST EN 50405:2007
Železniške naprave - Sistemi za odjem toka - Odjemniki toka, preskusne metode za
kontaktne drsnike
Railway applications - Current collection systems - Pantographs, testing methods for
contact strips
Bahnanwendungen - Stromabnahmesysteme - Stromabnehmer für
Oberleitungsfahrzeuge, Prüfverfahren für Schleifstücke
Applications ferroviaires - Systèmes de captage de courant - Méthodes d'essais des
bandes de frottement des pantographes
Ta slovenski standard je istoveten z: EN 50405:2015
ICS:
29.280 (OHNWULþQDYOHþQDRSUHPD Electric traction equipment
45.020 Železniška tehnika na Railway engineering in
splošno general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 50405
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2015
ICS 29.280 Supersedes EN 50405:2006
English Version
Railway applications - Current collection systems - Pantographs,
testing methods for contact strips
Applications ferroviaires - Systèmes de captage de courant Bahnanwendungen - Stromabnahmesysteme -
- Méthodes d'essais des bandes de frottement des Stromabnehmer für Oberleitungsfahrzeuge, Prüfverfahren
pantographes für Schleifstücke
This European Standard was approved by CENELEC on 2015-11-16. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2015 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 50405:2015 E
Content . Page
European foreword . 5
Introduction . 6
1 Scope . 7
2 Normative references. 7
3 Terms and definitions . 7
3.1 General . 7
3.2 Contact strip material . 8
3.3 Contact strip construction . 8
4 Symbols and abbreviations . 9
5 Requirements for data sheets .10
5.1 Data sheet and design drawing .10
5.2 Contact strip material .10
5.3 Contact strip characteristics .10
6 Test categories and environmental conditions .11
6.1 General .11
6.2 Type tests .11
6.3 Routine tests .11
6.4 Environment .11
6.5 Ambient air temperature .11
6.6 Test sequence .12
7 Test procedures .16
7.1 Tests for the temperature characteristic of the contact strip under current loading .16
7.1.1 General .16
7.1.2 Test method – To determine the temperature characteristic of the contact strip under current
loading .16
7.2 Test for deflection and extension of the carbon contact strip under extremes of
temperature .17
7.2.1 General .17
7.2.2 Test method - High temperature test .17
7.2.3 Test method - Low temperature test .18
7.3 Test for flexural characteristic of the contact strip .18
7.3.1 General .18
7.3.2 Test method .18
7.3.3 Test acceptance criteria .19
7.4 Test for shear strength of the contact strip .19
7.4.1 General .19
7.4.2 Test method - Test at ambient temperature .20
7.4.3 Test method - Test at specified temperature .22
7.5 Test of auto-drop detection sensor integral with contact strips .22
7.5.1 General .22
7.5.2 Test method - Sealing integrity .22
7.5.3 Test method - Sealing integrity temperature test.23
7.5.4 Test method – Air flow continuity .24
7.5.5 Test method - Impact function of the auto-drop detection sensor .24
7.6 Test of mechanical fatigue resistance of the contact strip .26
7.6.1 General .26
7.6.2 Test method .26
7.7 Test of the electrical resistance of the contact strip .27
7.7.1 General .27
7.7.2 Test method .27
7.8 Test of the metal content for metal impregnated (metalized) contact strips .28
7.8.1 General .28
7.8.2 Method 1: Weighing a part before and after the impregnation .28
7.8.3 Method 2: Determination of the apparent density of the material before and after the impregnation
...................................................................................................................................................29
7.9 Test of the coefficient of friction .29
7.9.1 General .29
7.9.2 Test method .29
7.10 Optional test of the impact resistance of the Carbon material .30
7.10.1 General .30
7.10.2 Test method .30
7.11 Test of the thermal fatigue properties of the contact strip .30
7.11.1 General .30
7.11.2 Test method - Thermal fatigue test .30
Annex A (informative) Parameters to be specified by the customer and graphical representation
of customer specified values for pantograph automatic dropping device operation .32
A.1 Parameters to be specified by the customer .32
A.2 Graphical representation of customer specified values for pantograph automatic dropping
device operation .33
Annex B (normative) Current loading test apparatus .34
B.1 Current loading test apparatus – copper test electrode .34
B.2 Current loading test apparatus .35
Annex ZZ (informative) Correspondence between this European Standard and the Essential
Requirements of EU Directive 2008/57/EC .36
Bibliography .37

Figures
Figure 1 — High temperature test apparatus . 17
Figure 2 — Flexural characteristics test apparatus . 19
Figure 3 — Shear test sample preparation . 20
Figure 4 — Shear test fixture example . 21
Figure 5 — Shear test apparatus example . 21
Figure 6 — Impact test device example . 25
Figure 7 — Air supply and monitoring apparatus example . 26
Figure 8 — Electrical resistance test apparatus example . 28
Figure A.1 — Graphical representation of customer specified values for pantograph
automatic dropping device operation . 33
Figure B.1 — Current loading test apparatus – copper test electrode . 34
Figure B.2 — Current loading test apparatus . 35

Tables
Table 1 ― Schedule of tests. 13
Table 2 ― Sequence of tests . 15
Table 3 ― Test current . 16
European foreword
This document (EN 50405:2015) has been prepared by CLC/SC 9XB "Electromechanical material on board
of rolling stock".
The following dates are fixed:
• latest date by which this document has (dop) 2016-11-16
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2018-11-16
standards conflicting with this
document have to be withdrawn
This document supersedes EN 50405:2006.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent
rights.
This document has been prepared under a mandate given to CENELEC by the European Commission and
the European Free Trade Association, and supports essential requirements of EU Directive(s).
For the relationship with EU Directive(s) see informative Annex ZZ, which is an integral part of this
document.
Introduction
This European Standard defines testing methods for pantograph contact strips, but excludes wear tests,
and tests using a particular pantograph.
In this issue of the standard, additional clauses have been included to address the European Rail Agency
(ERA) request for standard (IU-RFS-024 of 3rd July 2009) which requested that this standard specifies the
assessment methods for contact strips of different materials as specified in the High Speed and
Conventional Rail Locomotives and Passenger rolling-stock technical specifications for interoperability
(LOC and PAS TSIs). A method for determining the metal content for metal impregnated (metalized)
contact strips (7.8) has been added in this issue of the standard. Tests for the coefficient of friction (7.9)
and impact resistance of the carbon material (7.10) have also been included in this revision.
The Locomotives and Passenger rolling-stock technical specification for interoperability (COMMISSION
REGULATION (EU) No 1302/2014 of 18 November 2014) (LOC and PAS TSI) chapter 4.2.8.2.9.4.2 states:
4.2.8.2.9.4.2 Contact strip material
(1) Material used for the contact strips shall be mechanically and electrically compatible
with the contact wire material (as specified in Clause 4.2.14 of the ENE TSI, in order to
ensure proper current collection and to avoid excessive abrasion of the surface of the
contact wires, thereby minimising wear of both contact wires and contact strips.
(2) Plain carbon or impregnated carbon with additive material shall be permitted.
Where a metallic additive material is used, the metallic content of the carbon contact
strips shall be copper or copper alloy and shall not exceed a content of 35 % by weight
where used on AC lines and of 40 % where used on DC lines.
Pantographs assessed against this TSI shall be fitted with contact strips of a material
mentioned above.
(3) Additionally, contact strips of other material or higher percentage of metallic contents or
impregnated carbon with cladded copper are allowed (if permitted in the infrastructure
register) provided that:
— they are referenced in recognised standards, with mention of restrictions if any, or
— they have been subject to a test of suitability for use (see 6.1.3.8).
Evidence from the UIC project “COSTRIM” testing of a sample of carbon contact strips has shown the
difficulty of defining a cross-industry wear test. This could be the subject of a new requirement following
further analysis of the COSTRIM results for a future revision of this standard. (These values were
determined as a result of the tests undertaken under the COSTRIM project, and are the limit of the tests
carried out, rather than an absolute limit.)
Although not currently applicable to contact strips for railway applications, it should be noted that certain
materials listed in the EU Directive on the Restriction of the Use of Certain Hazardous Substances in
Electrical and Electronic Equipment 2011/65/EU are prohibited from use in certain applications
1 Scope
This European Standard specifies testing methods to establish the basic characteristics of newly
manufactured pantograph contact strips. Not all tests may be relevant to some designs of contact strips.
This standard does not define tests for pure metallic contact strips.
This European Standard excludes wear tests, and tests using a particular pantograph. Additional
supplementary tests, out of the scope of this standard, may be necessary to determine suitability for a
particular application and are by prior agreement between customer and manufacturer.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN ISO 148-1:2010, Metallic materials — Charpy pendulum impact test — Part 1: Test method (ISO 148-
1:2009)
EN ISO 179-1:2010, Plastics — Determination of Charpy impact properties — Part 1: Non-instrumented
impact test (ISO 179-1:2010)
EN ISO 180:2000, Plastics — Determination of Izod impact strength (ISO 180:2000)
IEC 60413:1972, Test procedures for determining physical properties of brush materials for electrical
machines
IEC 60773:1983, Test methods and apparatus for measurement of the operational characteristics of
brushes
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 General
3.1.1
air flow continuity
uninterrupted flow of air
3.1.2
air flow rate
flow rate, in standard litres per minute, based upon mass flow to be calculated at the standard temperature
and pressure (STP)
Note 1 to entry: Referenced at a temperature of 15 °C (288,15 K, 59 °F) and an absolute pressure of 101,325 kPa
(1,013 25 bar, 1 standard atmosphere (atm)).
Note 2 to entry: Based upon the Standard Temperature and Pressure defined by EN ISO 13443:2005.
3.1.3
auto-drop detection sensor
function incorporated in the contact strip which initiates the pantograph automatic dropping device
Note 1 to entry: The tests specified in this standard relate only to pantograph automatic dropping devices operated by
air pressure.
3.1.4
pantograph automatic dropping device
device intended to lower the pantograph automatically if it should be damaged
[SOURCE: IEC 60050-811:1991, 811-32-22]
3.1.5
rated current
current value that the contact strip is designed to sustain indefinitely without degradation under the
specified operating and environmental conditions
3.1.6
shear strength
force which can be withstood without failure of the adhesion between the carbon strip and the integral
carrier
3.2 Contact strip material
3.2.1
metal contact strip
strip of metal or metal alloys without carbon as a functional element
3.2.2
metal impregnated (metalized) carbon
plain carbon strips where the cavities are filled with metal or metal alloys
Note 1 to entry: The degree of impregnation is defined in percentage of weight.
Note 2 to entry: The material can contain additives and can be impregnated with oil, wax or resin.
3.2.3
plain carbon
hard carbon material, without added metal and consisting of a mixture of amorphous and graphite carbon
elements
Note 1 to entry: The material can contain additives and can be impregnated with oil, wax or resin.
3.3 Contact strip construction
NOTE The designs described in 3.3 may or may not include any of the following:
- Auto-drop detection sensor
- Integrated End Horns
- Arc Protection; either with additional components or coatings or with the carbon enshrouding the supporting carrier
3.3.1
bonded carbon contact strip
contact strip formed by a carbon contact strip permanently attached to an integral carrier by an adhesive
3.3.2
carrier
structure which supports the contact strip, but is not permanently attached to it, and is used as an interface
to the pantograph head
3.3.3
copper clad contact strip
carbon contact strip housed in a formed copper sheath, with copper on the leading and trailing faces
extending from the base to the contact surface of the carbon
Note 1 to entry: Often referred to as a “Kasperowski” contact strip.
3.3.4
fitted carbon contact strip
contact strip formed by a carbon contact material permanently attached to an integral carrier without the
application of adhesive or solder
Note 1 to entry: This includes, but is not exclusive to, designs with carbon crimped, rolled or pressed into a carrier.
3.3.5
integral carrier
structure which supports the contact strip without the need for any additional support between the mounting
points used to interface to the pantograph head and permanently attached to the contact strip
3.3.6
metal and carbon composite contact strip
contact strip formed by vertical layers of metal mixed with layers of carbon permanently attached to a
carrier
3.3.7
self-supported
contact strip which does not need additional support between the mounting points used to interface the
contact strip and the pantograph
3.3.8
soldered carbon contact strip
contact strip formed by a carbon contact strip permanently attached to an integral carrier by solder
3.3.9
un-supported
contact strip which requires mounting to an additional support structure (a carrier) before fitting to the
pantograph
4 Symbols and abbreviations
A
designed area of adhesion (mm )
F shear force (N)
S
R
resistance (Ω)
Τ shear strength (N/mm )
s
µ
coefficient of friction
T maximum temperature of the contact strip at the interface between the carrier
cs
and the “wearing material” determined by test (see 7.1) (°C). The temperature
is measured in the “wearing material” immediately adjacent to the interface.
T the limit temperature at which the shear strength of the bond maintains a
max
minimum value determined by test (see 7.4.3) (°C). (For bonded carbon
contact strips). The temperature is measured in the carbon immediately
adjacent to the interface.
W weight of the part before impregnation
b
W weight of the part after impregnation
a
AD apparent density of the specimen before impregnation
b
AD apparent density of the specimen after impregnation
a
Δh vertical deflection in the middle of the contact strip (Deflection upwards is
positive)
Δl change in length of the contact strip assembly (Increase in length is positive)
F test contact force (test 7.1.2.)
5 Requirements for data sheets
5.1 Data sheet and design drawing
The essential characteristics of the contact strip material shall be provided in a data sheet and design
drawing containing as a minimum the following information:
5.2 Contact strip material
1. manufacturer's grade designation;
2. hardness according to IEC 60413;
3. density according to IEC 60413;
4. flexural strength according to IEC 60413;
5. electric resistivity according to IEC 60413;
6. percentage of metal impregnation according to 7.8, with tolerance;
7. coefficient of friction according to 7.9;
8. material type e.g. plain carbon.
NOTE For metal contact strips information is provided according to alternative relevant standards.
5.3 Contact strip characteristics
1. contact strip construction as defined in 3.3 and Table 1;
2. data sheet and drawing reference numbers;
3. record of standard compliance and certification;
4. dimensions, tolerances and design drawings including specific requirements;
5. weight (new and fully worn) with tolerances;
NOTE 1 The worn weight, if provided, is an estimate based upon the service conditions.
6. designed rated current in operation;
7. wear limit;
value of T determined by test 7.1;
8.
cs
9. value of T determined by test 7.4.3;
max
10. maximum and minimum operating pressure for use with a pantograph automatic
dropping device;
11. air flow rate (in standard litres per minute) at minimum pressure for use with a
pantograph automatic dropping device;
12. minimum air leakage flow rate (in standard litres per minute) at specified pressure,
corresponding to auto-drop operation;
NOTE 2 This parameter relates to EN 50206-1:2010, 4.8. The value is given by the pantograph manufacturer to the
carbon contact strip manufacturer to use in the test of the auto-drop detection shock Impact function test set out in
7.5.5.
13. minimum air flow rate (in standard litres per minute) at specified pressure, for
operation of auto-drop detection sensor.
NOTE 3 This parameter is defined to permit compliance with the time of 1 s mentioned in EN 50206-1:2010, 6.2.5
for a specified pantograph. The value is given by the pantograph manufacturer to the carbon contact strip manufacturer
to use in the air flow continuity test set out in 7.5.4.
6 Test categories and environmental conditions
6.1 General
There are two categories of tests:
– type tests,
– routine tests.
Additional supplementary tests, out of the scope of this standard, may also be undertaken if they have
been specified in the customer specification and agreed with the manufacturer.
6.2 Type tests
Type tests shall be performed on samples of a given design, in accordance with the schedule of tests set
out in Table 1 and Table 2.
Designs in current manufacture shall be considered to have satisfied the type tests if the manufacturer can
provide certified reports of type tests (complying with the test requirements set out in this standard) which
have already been conducted successfully on identical components.
NOTE EN 50206-1:2010, 6.13.3 includes a combined test carried out by the customer during the running test of
the pantograph on the vehicle.
6.3 Routine tests
Routine tests shall be carried out in accordance with the schedule of tests set out in Table 1, to verify that
the properties of a product correspond to those determined during the type test. Routine tests shall be
performed on each item of equipment supplied, unless sampling is specified by the customer.
6.4 Environment
The test shall be made indoors in an environment substantially free from air currents, except those
generated by heat from the sample being tested. In practice, this condition is reached when the air velocity
does not exceed 0,5 m/s.
6.5 Ambient air temperature
The ambient air temperature is the average temperature of the air surrounding the sample. It shall be
recorded during the tests.
The ambient air temperature during tests shall be more than +15 °C but shall not exceed +30 °C. No
correction of the temperature-rise values shall be made for ambient air temperatures within this range.
All tests shall be carried out at ambient temperature unless otherwise specified.
6.6 Test sequence
Tests shall be performed in the sequence defined in Table 2 using the same sample for successive tests as
indicated in each column of the table.
NOTE The test sequence has been set out in Table 2 to minimize the number of samples required for testing.
Sample A is subject to a comprehensive series of tests to demonstrate capability of withstanding stresses the contact
strips experience in service. A minimum of four sample contact strips plus material samples will be needed to complete
the full series of tests.
Table 1 — Schedule of tests
Routine
Type Tests
Tests
Metal and Carbon
Bonded Carbon Soldered Carbon Fitted Carbon Copper Clad Metal Contact
Design Composite
Contact Strips Contact Strips Contact Strips Contact Strips Strips
Contact Strips
Self- Un- Self- Un- Self- Un- Self- Un- Self- Un- Self- Un-
Test Support suppor Support support Support support Support support Support support Suppor suppor

ed ted ed ed ed ed ed ed ed ed ted ted
7.1 Temperature
characteristic under rated Yes Yes Yes Yes Yes Yes No
current loading
7.2 Deflection and
extension under extremes Yes Yes Yes Yes Yes Yes No
of temperature
7.3 Flexural characteristic Yes No Yes No Yes No Yes No Yes No Yes No
Yes (if bonded or
e
7.4 Shear strength Yes Yes No No No
soldered)
7.5.2 Pantograph
a a a a a a a
automatic dropping Yes Yes Yes Yes Yes Yes R
device Sealing integrity
7.5.3 Pantograph
a a a a a a
automatic dropping Yes Yes Yes Yes Yes Yes
device temperature test
7.5.4 Pantograph
a a a a a a a
automatic dropping Yes Yes Yes Yes Yes Yes R
device air flow continuity
7.5.5 Impact function of the a a,c a a,c a a,c a,b,c a a,c a,b,c
Yes Yes Yes Yes Yes Yes No Yes Yes No
auto-drop detection sensor
7.6 Mechanical fatigue
Yes No Yes No Yes No Yes No Yes No Yes No
resistance
Yes (if bonded or
R (bonded
7.7 Electrical resistance Yes Yes (type test only) Yes (type test only) Yes (type test only) soldered – type No
only)
test only)
7.8 Metal content for metal
Yes (for carbon Yes (for carbon
impregnated contact
Yes Yes Yes No
part) part)
strips
7.9 Test of the coefficient Yes (for carbon Yes (for carbon
f
Yes Yes Yes No
of friction part) part)
7.10 Optional test of the
d d d d d
Impact resistance of the
No No No No No No
Carbon material
7.11 Test of the thermal
Yes (if bonded or
fatigue properties of the Yes Yes No No No
soldered)
contact strip
a
Denotes test that is only required if the strips are fitted with a pantograph auto-drop detection sensor.
b
The impact energy required to cause sufficient damage for activation of the pantograph auto-drop detection sensor with a copper clad strip or metal strip is extremely
high when compared to the energy with a bonded or soldered carbon. Manufacturer and customer to determine if this test is appropriate for this type of contact strip.
c
For unsupported contact strips, the performance of the pantograph automatic dropping device may be dependent upon the carrier mounted on the pantograph. The
test is done on the complete assembly. The customer is responsible for providing the additional supporting components necessary to undertake this test.
d
Optional test to be undertaken only if specifically requested by the customer.
e
If carrier is sufficiently large to clamp into test apparatus.
f
For metal contact strips information shall be provided according to alternative relevant standards.
Table 2 — Sequence of tests
Individual
Design Sample A Sample B Sample C Sample D material
samples
Test Test
Test Test sequence Test sequence
sequence sequence
7.1 Temperature characteristic 4

under rated current loading
7.2 Deflection and extension 5

under extremes of temperature
3 (with
7.3 Flexural characteristic
7.5.2)
14 (at ambient
temperature as 1 (7.4.2) and
7.4 Shear strength
specified in (7.4.3)
7.11)
2, 9 and 12
7.5.2 Pantograph automatic 2, 5 (at wear
dropping device Sealing integrity limit)
7.5.3 Pantograph automatic 6
dropping device Temperature test
7.5.4 Pantograph automatic
3 and 13
dropping device air flow 4 3
continuity
7.5.5 Impact function of the auto-
drop detection sensor
7.6 Mechanical fatigue resistance
1, 8 and 11
7.7 Electrical resistance 1 1
7.8 Metal content for metal
Material sample
a
impregnated contact strips
7.9 Test of the coefficient of
Material sample
a
friction
7.10 Test of the Impact resistance
Material sample
a
of the Carbon material
7.11 Test of the thermal fatigue 10

properties of the contact strip
a
Material samples need not be obtained from a finished contact strip.
7 Test procedures
7.1 Tests for the temperature characteristic of the contact strip under current loading
7.1.1 General
The test determines the temperature within the contact strip when carrying a defined current, T which
cs
is used as a reference temperature in subsequent tests. If the value of T measured in this test is less
cs
than 100 °C, then a value of 100 °C shall be used in the subsequent tests.
This test demonstrates that the strip design achieves dissipation of energy under current loading so
that the maximum design temperature limit is not exceeded when thermal equilibrium is reached.
Continuous measurement of the temperature shall be used to determine the steady temperature
reached at the defined current loading.
This test will allow comparisons between manufacturers by the use of a standard test.
This test shall be carried out at ambient temperature (see 6.5).
7.1.2 Test method – To determine the temperature characteristic of the contact strip under
current loading
The test shall determine the temperature T , within the contact strip when carrying a defined current.
cs
A current, selected from the values given in Table 3, shall be passed from a standard test electrode
into the top surface of the contact strip under test, and the current shall return through the normal
electrical connection points of the contact strip.
Table 3 — Test current
AC contact strip plain carbon contact strip 300 A
test current
metal impregnated carbon contact strip 300 A
other types of contact strip 300 A
DC contact strip plain carbon contact strip 300 A
test current
metal impregnated carbon contact strip 10 A per mm of contact strip width
other types of contact strip 600 A
The shape of the copper test electrode shall be as shown in Figure B.1. The contact strip shall be
ground flat over the area in contact with the copper test electrode, which shall be held in contact with
the contact strip with a maximum test contact force (F) of 1 500 N. The number and position of current
connections shall be such that the current is evenly distributed through the copper test electrode. The
arrangement of the test apparatus and temperature measurement point are as shown in Figure B.2.
The same design of electrode is used for both for AC and DC applications.
NOTE 1 This current value is for test purposes only and does not reflect the declared operational design limits
for the contact strip. The test values and test arrangements have been determined through trials undertaken by
manufacturers supporting the working group.
NOTE 2 The test contact force is for test purposes only. If necessary the contact strip carrier may be
reinforced to achieve the required contact force.
NOTE 3 The copper test electrode is specified for test purposes only. Results from this copper test electrode
have been verified by comparison with results obtained in service.
7.2 Test for deflection and extension of the carbon contact strip under extremes of
temperature
7.2.1 General
This test determines the vertical deflection and the change in length of the contact strip assembly
under the influence of extreme temperatures.
NOTE This test can be applied to contact strips forming the centre part of the pantograph head while being
integrated into a pantograph head construction forming the outer contour. In this case, it can be important that the
change in geometry remains within limits set out in the design.
7.2.2 Test method - High temperature test
7.2.2.1 General
This test determines the changes in geometry of the strip when heated to the temperature T and
cs
shall demonstrate that these deflections remain within the elastic limit and the deformations are
compatible with the technology of assembly of the pantograph head.
The temperature of the contact strip shall be raised to T . Measurements shall be taken when the
cs
temperature becomes steady.
The change in length of the contact strip assembly (Δl) and the vertical displacement in the middle of
the strip (Δh) in reference to the position at ambient temperature (see 6.5) shall be measured and
recorded (see Figure 1) along with the ambient and contact strip temperature.

Key
(1) fixed end support at mounting interface position
(2) vertical deflection (∆h) in the centre of the contact strip (deflection upwards is
positive)
(3) change in length (∆l) of the contact strip (increase in length is positive)
(4) free end support at mounting interface position
Figure 1 — High temperature test apparatus
7.2.2.2 Test acceptance criteria
The dimensions h and l shall stay within the values defined on the design drawing after returning to
ambient temperature (see 6.5). Δh and Δl shall be measured and recorded together with the ambient
and contact strip temperature.
After cooling to ambient temperature (see 6.5) the contact strip assembly shall be undamaged. The
contact strip is considered to be undamaged if a visual inspection confirms no fissures are visible. In
case of plain carbon, metal impregnated or metal clad carbon strips no fissures shall be visible in the
contact material or near the bonding surface. The regular current transmission points including fixing
points do not show any sign of thermal overheating.
NOTE The sealing integrity test defined in 7.5.3.1 may be combined with this test.
7.2.3 Test method - Low temperature test
7.2.3.1 General
This test shall be undertaken after test 7.2.2 on the same samples.
The contact strip shall be cooled until the temperature of the strip is -25 °C or the minimum
temperature as specified by the customer. Δh and Δl shall be measured and recorded together with
the ambient and contact strip temperature.
NOTE The minimum temperature of -25 °C is based upon category T1 in EN 50125–1.
7.2.3.2 Test acceptance criteria
The dimensions h and l shall stay within the values defined in the design drawing after returning to
ambient temperature (see 6.5). Δh and Δl shall be measured and recorded together with the ambient
and contact strip temperature. There shall be no visible fissures and no permanent deformation.
NOTE The sealing integrity test defined in 7.5.3.2 may be combined with this test.
7.3 Test for flexural characteristic of the contact strip
7.3.1 General
This test determines the flexural characteristic of the contact strip at ambient temperature (see 6.5).
7.3.2 Test method
The flexural characteristic (in graphical form) shall be determined by three point bending of the
complete contact strip when freely supported at the normal mounting points at each end of the strip
along the longitudinal centreline of the contact strip and loaded vertically at the centre (e.g. by
hydraulic or mechanical press). The radius of the force applicator shall be at least 4 mm. The direction
of the force shall be perpendicular to the contact face. The force shall be steadily increased.
The minimum force used for the measurement shall be 350 N. If the linear part of the deformation
curve is not reached, the force shall be increased until the linear characteristic is shown.
The force may be increased to the point of permanent deformation of the contact strip.
Key
(1) free supports at mounting interface positions
(2) vertical deflection (∆h) in the centre of the contact strip (deflection
upwards is positive)
(3) force (F) applied perpendicular to contact strip at centre
Figure 2 — Flexural characteristics test apparatus
7.3.3 Test acceptance criteria
The test results shall show that the contact strip remains within the elastic limit with a minimum force
of 350 N applied.
The contact strip is considered to be undamaged if a visual inspection confirms no fissures are visible
following a test with a force of up to a minimum of 350 N applied.
7.4 Test for shear strength of the contact strip
7.4.1 General
7.4.1.1 Introduction
This test demonstrates that the interface between carbon and integral carrier meets the minimum
shear strength criteria:
i. At ambient temperature (see 6.5),
ii. At the temperature T
cs
iii. At specified temperatures ( see 7.4.3),
iv. After being subjected to thermal fatigue (see 7.11).
This test shall demonstrate that the adhesion between carbon and supporting structure meets the
minimum shear strength criteria at ambient temperature, at th
...